Zigzag transition of finite dust clusters

Experiments on the zigzag transition of finite dust clusters are presented. There, microspheres have been confined in an anisotropic trap in the sheath of a radio-frequency discharge plasma. Transitions of the clusters from a linear chain into a zigzag configuration are observed by increasing the particle number in the chain or by variation of the anisotropy of the confinement. The equilibrium configurations of the finite clusters, as well as the dynamical properties and the stability behavior near the transition have been investigated from a normal mode analysis. Furthermore, the longitudinal and transverse dispersion of the normal modes in the one-dimensional (1D) chain has been derived